Objective To investigate characteristics of cage migration after transforaminal lumbar interbody fusion (TLIF) and related risk factors.Methods A retrospective study was conducted to review cage migration in 512 patients who had undergone TLIF procedure from January 2010 to June 2011 in 5 spinal research centers.There were 255 males and 257 females,aged from 37 to 77 years (average,54.7 years).All patients were followed up at 3,6,12 months after operation.The clinical outcomes were evaluated using the visual analogue scores (VAS) and Oswestry disability index (ODI).X-rays and 3D CT scans were used to analyze the incidence and related risks factors of cage migration in these patients.Results Cage migration was found in 6 of 512 patients,the total incidence was 1.17％.Significant difference was found between each center.Cages with different shapes had different incidence.The analysis showed that the incidence of migration of rectangular-shaped cage (3.11％,5/161) was significantly higher than that of kidney-shaped cage (0.28％,1/351).The cage in double-segment TLIF (5.75％,5/87) was easier to migrate than that in monosegment TLIF (0.24％,1/425); furthermore,linear type endplate(3.50％,5/143) was remarkably easier to migrate than concave-concave one (0.27％,1/369).Conclusion Difference in operative skills,cage shape,number of fused segments,adjacent endplate shape,and lumbar spondylolisthesis might be risk factors for cage migration after TLIF.